David Lammy has been doing some really great work on highlighting economic inequality in the UK, and this is no exception, but I disagree with his use of the word "shocking" to describe the results. It's not even remotely surprising that students from wealthier families are more likely to end up at top universities - they're far more likely to have parents who can afford to live in areas with good schools, or to send them to private school, or top state schools outside their area. They're also more likely to be able to access private tuition for admissions tests, or programmes that offer interview coaching etc. Their schools will have a number of people applying to Oxbridge every year, and so will know how to support them through the process. A student from a low income family is more likely to go to a struggling school, with much less access to support and coaching, and often less encouragement to actually apply in the first place. They're also more likely to be the first person in their family to go to university, meaning that their parents may be less able to guide them through the application process than parents who have experienced that process themselves, or with other children in their family.
Is this an appalling situation which needs to change? Absolutely. But, deep down, at least, we all already knew that.